GB1473878A - Telephone ringing circuits - Google Patents
Telephone ringing circuitsInfo
- Publication number
- GB1473878A GB1473878A GB2887874A GB2887874A GB1473878A GB 1473878 A GB1473878 A GB 1473878A GB 2887874 A GB2887874 A GB 2887874A GB 2887874 A GB2887874 A GB 2887874A GB 1473878 A GB1473878 A GB 1473878A
- Authority
- GB
- United Kingdom
- Prior art keywords
- thyristor
- frequency
- ringing
- june
- capacitor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04M—TELEPHONIC COMMUNICATION
- H04M19/00—Current supply arrangements for telephone systems
- H04M19/02—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone
- H04M19/04—Current supply arrangements for telephone systems providing ringing current or supervisory tones, e.g. dialling tone or busy tone the ringing-current being generated at the substations
Landscapes
- Engineering & Computer Science (AREA)
- Signal Processing (AREA)
- Devices For Supply Of Signal Current (AREA)
- Mobile Radio Communication Systems (AREA)
Abstract
1473878 Ringing circuits J M PERSON and J M GARNIER 28 June 1974 [28 June 1973] 28878/74 Heading H4K In a telephone ringing circuit an oscillator 3 operates a switch 4 to periodically discharge a capacitor 221 connected across a transducer 5, the capacitor being charged from rectified ring- ing current via a voltage doubler 1, and a constant current circuit involving Zener diode 223. The switch 4 is preferably a thyristor. The frequency at which the thyristor is switched determines the sound frequency produced, this frequency being governed by the control voltage of the thyristor and components 32, 33, 36, 37. Variable resistor 225 can be used as a volume control for the ringing signal.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FR7323710A FR2235556B1 (en) | 1973-06-28 | 1973-06-28 |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1473878A true GB1473878A (en) | 1977-05-18 |
Family
ID=9121721
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB2887874A Expired GB1473878A (en) | 1973-06-28 | 1974-06-28 | Telephone ringing circuits |
Country Status (4)
Country | Link |
---|---|
US (1) | US3919493A (en) |
DE (1) | DE2427042C3 (en) |
FR (1) | FR2235556B1 (en) |
GB (1) | GB1473878A (en) |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE435777B (en) * | 1979-01-29 | 1984-10-15 | Ibuki Kogyo Co Ltd | ELECTRIC HORN |
JPS56501185A (en) * | 1979-08-20 | 1981-08-20 | ||
US5172408A (en) * | 1990-08-01 | 1992-12-15 | At&T Bell Laboratories | Speakerphone state-controlled alerting arrangement |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3471651A (en) * | 1967-01-13 | 1969-10-07 | Ibm | Telephone ringing circuit |
US3539732A (en) * | 1967-03-18 | 1970-11-10 | Carlos Weissenberg | Electronic system for signaling the entrance of telephone calls in multiline telephone sets |
FR1581035A (en) * | 1968-07-08 | 1969-09-12 | ||
US3536852A (en) * | 1969-01-23 | 1970-10-27 | Lorain Prod Corp | Telephone interruption switching circuitry |
US3603740A (en) * | 1969-08-18 | 1971-09-07 | Northern Electric Co | Method and means for ringing a telephone subset |
US3688038A (en) * | 1971-04-12 | 1972-08-29 | Stromberg Carlson Corp | Stored energy signalling circuit |
-
1973
- 1973-06-28 FR FR7323710A patent/FR2235556B1/fr not_active Expired
-
1974
- 1974-06-03 US US476064A patent/US3919493A/en not_active Expired - Lifetime
- 1974-06-05 DE DE2427042A patent/DE2427042C3/en not_active Expired
- 1974-06-28 GB GB2887874A patent/GB1473878A/en not_active Expired
Also Published As
Publication number | Publication date |
---|---|
FR2235556B1 (en) | 1978-09-08 |
FR2235556A1 (en) | 1975-01-24 |
DE2427042B2 (en) | 1977-08-18 |
US3919493A (en) | 1975-11-11 |
DE2427042A1 (en) | 1975-01-30 |
DE2427042C3 (en) | 1978-04-13 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed [section 19, patents act 1949] | ||
PCNP | Patent ceased through non-payment of renewal fee |